Recent Advances in Photocatalytic Urea Synthesis via C−N Coupling From C/N-Containing Species: A Mini Review

Abstract

Conventional industrial urea synthesis requires processes that operate under high-temperature and high-pressure conditions, which are energy-intensive and result in substantial environmental pollution. In contrast, photocatalytic C–N coupling has emerged as a promising green and sustainable alternative, enabling urea production from various carbon and nitrogen sources through co-reduction under ambient conditions. When powered by renewable energy, this approach holds significant potential to advance sustainable development and has consequently attracted increasing research interest in recent years. This review systematically summarizes recent advances in photocatalytic urea synthesis using diverse carbon sources (CO₂, CO, CH₃OH) and nitrogen sources (N₂, NH₃, NO₃⁻). Mechanistic insights into the C–N coupling pathways involved in these processes are discussed in this review, with the aim of guiding future research toward improving urea yield. Furthermore, the key challenges in photocatalytic urea synthesis are critically examined, along with potential strategies to address these limitations. Overall, this review aims to provide strategic guidance for the rational design of efficient photocatalysts and the development of advanced approaches to enhance the performance of photocatalytic urea production.

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